Conventionally, blood and human metabolites (urine and feces) have been major clinical items used for determining human health condition. Recently, saliva and expired gas have been becoming test objects, and sweat will be also included in such clinical items in future. Components of such expired gas, saliva, and sweat depend on components of blood and thus there is quantitative relationship between both the components. It is expected that these noninvasive metabolites be used in the field of in-home medical care and health management in future.
There have been no measuring equipment used for clinical measurement and no measuring equipment for determining human health condition using such skin permeable gas. This is because the existence of the skin permeable gas itself has not been assumed for such purposes.